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by ptuomov
Sun Dec 26, 2021 6:00 pm
Forum: Electric & Hybrid Vehicle ** NEW **
Topic: Who here actually drives an EV/HYBRID?
Replies: 98
Views: 11026

Re: Who here actually drives an EV/HYBRID?

I personally daily drive AMG v8’s because I’m old and do a lot of longer ski trips in the northeast. In Finland, I drive a plug-in hybrid GLE 350 de because of its extreme range with battery and tank full, not available in the US. Just ordered a Tesla Model S Plaid as my daughter is getting a licens...
by ptuomov
Mon Nov 29, 2021 6:59 pm
Forum: Engine Tech
Topic: Camshaft Overlap@.050" vs Idle Quality
Replies: 30
Views: 2424

Re: Camshaft Overlap@.050" vs Idle Quality

I don’t know the answer to any of these questions, but I do have two thoughts or really further questions: First, for idle rpm (and throttle cracked cruise rpm) engine operating conditions, is it the seat overlap or the overlap at 0.05” that better predicts idle quality? Second, is the answer to th...
by ptuomov
Thu Nov 11, 2021 9:42 am
Forum: Engine Tech
Topic: So An Intercooler Actually Robs Power If Boost Is Too Low?
Replies: 11
Views: 733

Re: So An Intercooler Actually Robs Power If Boost Is Too Low?

At zero psi, the intercoolers reduces power because of its flow restriction. In practice, every gasoline powered engine can make more power with an intercooler than without an intercooler. So you can’t use the above limiting case to convince yourself that you wouldn’t benefit from / don’t need an in...
by ptuomov
Wed Nov 10, 2021 7:21 am
Forum: Engine Tech
Topic: Higher Compression Engine w/ Lower Turbo Boost
Replies: 27
Views: 1194

Re: Higher Compression Engine w/ Lower Turbo Boost

Why not put a small air to air intercoolers on the right hand side, in the same location where the turbo is on the left hand side? I would run the most compact log manifold possible to the turbo on the left hand side, then the dump pipe down and back also on the left hand side. The compressor outlet...
by ptuomov
Mon Nov 08, 2021 5:05 pm
Forum: Engine Tech
Topic: Higher Compression Engine w/ Lower Turbo Boost
Replies: 27
Views: 1194

Re: Higher Compression Engine w/ Lower Turbo Boost

Where are you placing the turbo? In front of the engine or behind the engine?
by ptuomov
Sun Nov 07, 2021 8:28 pm
Forum: Engine Tech
Topic: Higher Compression Engine w/ Lower Turbo Boost
Replies: 27
Views: 1194

Re: Higher Compression Engine w/ Lower Turbo Boost

Beyond controlling the manifold pressure to absolute (not gauge) pressure, here’s another altitude compensation idea: a tiny bit of nitrous oxide. When turbine has spooled and wastegate is partially open, the turbo compensation delivers the desired torque regardless of the altitude. However, at high...
by ptuomov
Sun Nov 07, 2021 12:05 am
Forum: Engine Tech
Topic: Higher Compression Engine w/ Lower Turbo Boost
Replies: 27
Views: 1194

Re: Higher Compression Engine w/ Lower Turbo Boost

If you’re interested in making similar power regardless of altitude or air density, you don’t need a higher compression ratio. Instead, you need a boost control that limits the boost such that the manifold absolute pressure is constant regardless of altitude. That is, a turbo compensated engine, lik...
by ptuomov
Fri Nov 05, 2021 11:27 am
Forum: Engine Tech
Topic: Turbo: Space Is Limited, How Terrible Is This Exhaust Flow?
Replies: 11
Views: 769

Re: Turbo: Space Is Limited, How Terrible Is This Exhaust Flow?

If you have 240 degree or longer exhaust blowdown pulse separation, any sort of compact log exhaust manifold will make more turbo power than a rider can handle.
by ptuomov
Wed Oct 06, 2021 10:19 am
Forum: Engine Tech
Topic: Fiat twincam project coming off the stand
Replies: 28
Views: 2178

Re: Fiat twincam project coming off the stand

Remind us what’s the highest redline rpm you’re comfortable with?
by ptuomov
Mon Oct 04, 2021 10:33 pm
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 76
Views: 4923

Re: It's all about the FUEL

Thinking about this a little more from the perspective of a street turbo car. Below the turbine spool rpm, one would need chemical oxidizer and fuel. Above the turbine spool rpm, one just needs higher octane to prevent knock. What’s the best solution here?
by ptuomov
Thu Sep 30, 2021 9:09 pm
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 76
Views: 4923

Re: It's all about the FUEL

In practice, what are peak power numbers for in a modern street turbo car? Bragging rights, mostly. So the practical (ok, stretching the meaning of the word here) application here would be an additional fuel component that could be run with minimal modifications but that would nevertheless give 10-2...
by ptuomov
Thu Sep 30, 2021 11:23 am
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 76
Views: 4923

Re: It's all about the FUEL

How much acetone does one have to mix in with E85 and nitromethane to keep it all mixed in well including that 15% of gasoline in E85?

Also, I wonder what nitromethane + acetone + ethanol + gasoline does to the turbine when the engine is run rich, anyone know?
by ptuomov
Thu Sep 30, 2021 7:39 am
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 76
Views: 4923

Re: It's all about the FUEL

Then let’s do the E85 trick with nitromethane and gasoline. “Nitropropane is not useful as a race fuel, unlike nitromethane. Nitropropane has the same specific energy as gasoline.“ Per unit of air ingested by the engine? I’m talking about an air limited engine. Nitropropane brings its own oxygen. Ni...
by ptuomov
Wed Sep 29, 2021 3:47 pm
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 76
Views: 4923

Re: It's all about the FUEL

I don’t know about the power increase. Smarter people can answer that question. My idea was simply to start with E85 and then add both racing gasoline and nitro in the right proportions in a way that allows one to keep the same carb jetting / fuel injector maps. Wonder if that would work? This engin...
by ptuomov
Wed Sep 29, 2021 11:30 am
Forum: Engine Tech
Topic: It's all about the FUEL
Replies: 76
Views: 4923

Re: It's all about the FUEL

“Nitropropane is not useful as a race fuel, unlike nitromethane. Nitropropane has the same specific energy as gasoline.“

Per unit of air ingested by the engine? I’m talking about an air limited engine. Nitropropane brings its own oxygen.